class Container {
	static of(value) {
		return new Container(value);
	}
	constructor(value) {
		this._value = value;
	}
	map(fn) {
		return Container.of(fn(this._value));
	}
}

class MayBe {
	static of(x) {
		return new MayBe(x);
	}
	isNothing() {
		return this._value === null || this._value === undefined;
	}
	constructor(x) {
		this._value = x;
	}
	map(fn) {
		return this.isNothing() ? this : MayBe.of(fn(this._value));
	}
}
module.exports = { MayBe, Container };
